Inhalt des Dokuments

Project B2: Collective
dynamics in colloidal model systems.

We
plan to further explore the potential of HI to induce novel motional
patterns in different settings. For example, we will add a
long-range repulsive potential between the circling particles
just mentioned and investigate how their nonlinear dynamics is
changed. We will also look at particles in a line, oscillating around
their mean positions, to see if HI synchronize the particles'
oscillations. This can have direct biological relevance for the
so-called metachronal waves in arrays of beating cilia.A
very challenging idea which also expresses a vision of this project
is to set up a minimal colloidal model system driven by external
fields that may exhibit chaotic behavior as, e.g., in the famous
Lorenz system. A system we will explore in this respect are two
magnetic beads that are linked by a spring and that are actuated from outside by a magnetic field.The HI will be treated with
the help of self- and cross-mobilities that depend on the particles' coordinates and that relate all the forces acting on the
particles to their velocities. We will solve these equations of
motions numerically to obtain a first insight into the dynamics
of the system and then try to extract non-linear dynamic equations that can be handled analytically with the help of
bifurcation analysis. Furthermore, we will perform Brownian
dynamics simulations to investigate how thermal noise influences
our findings.